Introduction:
An ordinary alarm switch is an electric switch which--when pressed--closes a circuit to operate a siren, a camera or any other warning device. The alarm circuit could also be connected to any security office or police station. Wireless sets carried by policemen, guards and other people who work in dangerous places may be looked at as an alarm switch when used to call for help. Even the pressing of a telephone's buttons can be likened to the use of an alarm switch when someone rings the police or the ambulance to call for help.
Problems encountered in the operation of ordinary alarm switches:
All the above types of alarm switches have various deficiencies. Following are some examples:
1-Using the switch at the critical time:
The victim is required to actuate the switch just before, or while being assaulted. He is supposed to do so at the very precious time he needs to defend himself or to escape. He may be in a situation that does not enable him to reach the alarm switch. Due to confusion, his attempt may further endanger his life.
2-Situations in which the use of the alarm switch is impossible:
It is sometimes impossible for the victim to actuate the switch if he is closely threatened, injured or actually assaulted. In situations such as unconsciousness, a telephone or an ordinary alarm switch becomes useless.
3-Ordinary alarm switches do not tell the difference between "suspicion" and "actual danger" states:
Many people are deterred from actuating the alarm switch when they suspect a stranger, for fear of embarrassment if nothing happens. A patient may likewise hesitate before calling for help for the same reason, although this may be dangerous. Alarm signals made for falsely suspecting a danger, may be very disturbing.
4-Signals transmitted to call for help are usually late:
In most cases no alarm signals are transmitted to a security office or a police station before an actual assault. Therefore, it is hard to provide assistance at the proper time. Late signals do not allow the monitoring of events on a TV circuit. To overcome such a problem, security guards need to be employed for 24 hrs/day, to guard houses or private premises; which is very costly. Late signals may cause problems in case of providing help or medical advice to a sick or injured person.